Video recently taken by a NASA research plane in Antarctica captured one such example, and the space agency posted it to Twitter.

The images provoked awe from social-media denizens -- as well as some suspicion, seeing as the iceberg looks, well, unnatural.

But the explanation for the tabular iceberg is simple enough:

The Larsen C ice shelf is truly massive, which means many parts of it are perfectly flat. The rectangular iceberg was one of those parts, and it recently sheared from the shelf. The iceberg is estimated to be around 130 feet tall and a mile or two long, National Geographic reports. It probably won't remain a near perfect rectangle for long.

"The [icebergs] detaching from Larsen C are so big, they look perfectly rectangular or with linear features," Jet Propulsion Lab research scientist Eric Rignot told the magazine, "because they were created from rifts that run across the ice shelf for hundreds of kilometers straight."

Scientists are paying close attention to Larson C because the Antarctic is heating up rapidly, and how it reacts to climate change will be instructive to the impacts on the rest of the planet.